Your motherboard will support ANY pci-e GPU as it is all backwards compatible.
In your case the MoBo is PCI-E 2.0 and the 9XX and 10XX cards are PCI-E 3.0 but as stated it is still backwards compatible.
Would be far more concerned about having a decent quality PSU. A good PSU will last through many upgrades and will handle running at max load no problem. A junk PSU shaped box has a sticker with a number on it that in no way means it can handle a sustained load at half that wattage; and when it dies it fries your GPU and motherboard.